Eating a healthy diet was linked with a lower risk of dying from heart disease, stroke, cancer, or other diseases among a population of low-income individuals living in the southeastern U.S., according to research led by Vanderbilt University investigators.
The study by first author Dr. Danxia Yu, Vanderbilt research fellow, and lead author Dr. Wei Zheng, director of the Vanderbilt Epidemiology Center and chief of the Division of Epidemiology, was published in the latest issue of the journal PLOS Medicine. Investigators from the International Epidemiology Institute, the Harvard School of Public Health, and Meharry Medical College were also involved in the study.
The investigators analyzed data from the Southern Community Cohort Study (SCCS) which includes 84,735 adults, aged 40–79, recruited from 2002–2009, mostly through community health centers serving low-income populations in 12 southeastern states. More than half of the participants had an annual household income of less than $15,000 and 65 percent were African American.
At the time of recruitment participants responded to a detailed food frequency questionnaire which noted the types and amounts of foods in their usual diet. For this follow-up study the investigators used the federal government’s Dietary Guidelines for Americans (DGA), and the Healthy Eating Index (HEI) to assess the healthfulness of the participants’ diets. The DGA emphasizes a diet rich in vegetables, fruits, whole grains, seafood, legumes, and nuts; moderate in low- or non-fat dairy and alcohol; and low in red and processed meats, sugar-sweetened foods and drinks, and refined grains.
Of the 77,572 participants with follow-up information over a mean period of 6.2 years, 6,906 participants died, including 2,244 from cardiovascular disease, 1,794 from cancer, and 2,550 from other diseases. After controlling for factors such as age, weight, exercise, smoking, and prior history of some chronic diseases, the investigators found that participants who ate the healthiest diet had an approximately 20 percent lower risk of death from those diseases than those with the least healthy diet.
The authors note that previous studies have suggested African Americans and low-socioeconomic adults, especially low-income African-American men, have more limited access to supermarkets and healthy foods and to have generally lower quality diets. However, few studies had evaluated the association between overall diet quality and disease mortality.
“This is the first study to our knowledge reporting this association in a low-income population that largely comprises African Americans,” says Dr. Zheng. “These findings present direct evidence that dietary modification may influence disease prevention in this underserved population.”